The present invention relates to a delivery bellows pump adapted to be applied on a bottle or a container for liquids such as soaps, detergents and so forth. The bellows pumps of the prior art are generally pumps in which the liquid sucked from the container is held in the pump body outside the container because the entire pump excepting the sucking tube, is arranged above the closing plug of the container.
If this constructional system on the one hand limits the space lost inside the container for arranging the pump device instead of liquid to be delivered, on the other hand the transposition of the pump body on the outer part on the container causes non-negligible drawbacks.
One of the main drawbacks is that after delivery, the liquid sucked by the bellows returning to the rest position, is held inside the pump body, therefore outside the container. Consequently if the container together with the relevant pump is moved from its vertical position, it may happen that the liquid comes out from the pump through the delivery duct without an explicit will to deliver liquid.
Clearly this is an important drawback limiting the positive features of the bellows pump, said features being highlighted by the fact that the bellows pump are generally made of plastic materials without metal members and therefore they can be fully recycled. Moreover the bellows pumps allow to make smaller containers with the same liquid contents because the room up to now used by the pump inside the container is now transposed on the container head.
Another drawback of the bellows pump however like other pumps for delivery of liquids from containers, consists in that unintentional impacts, undesired forces applied on the bellows head cause the pump to be actuated and therefore the liquid to be delivered.
Therefore there is the need to provide bellows pumps with devices preventing the accidental delivery of liquid by overturning the container and also the unintentional operation of the bellows.
The Japanese publication JP10101119-A discloses a bellows pump solving the problem of unintentional liquid discharge from the delivery duct by providing a valve arranged on said delivery duct. The same document provides also a further device consisting of an annular band arranged between the bellows push button and the pump body so as to prevent accidental movements of the bellows and the liquid delivery.
The drawback of such a device is that the bellows blocking ring must be applied or removed whenever the operation of the pump must be blocked, involving also the trouble to keep at disposal the ring as a detached part of the pump.
The object of the present invention is to overcome the above mentioned limits and drawbacks.
Indeed an object of the invention is to provide a bellows pump in which the delivery duct can be easily closed or opened according to the needs.
Another object to be obtained is a tight closure of the delivery duct so as to make loss of liquid from the container to the outside impossible.
Another object to be obtained is to provide a simple device for blocking the pump stroke which is always available.
Another object is to provide a bellows pump with a limited size, anyway with plan dimensions falling inside the diameter of the push button or the plug screwed on the container.
This has the object to make easier all the stockage and packing operations of the container provided with the pump of the invention, so that the overall dimensions are reduced to the minimum and at the same time the pump tightness is warranted.
A last but not least object is to carry out a bellows pump comprising few parts, that can be easily assembled with automatic machinery.
All the above indicated objects and others that will be better pointed out hereinafter are attained by a bellows pump for delivery of a liquid stored in a container, said pump being fixed to the container neck through a plug being part of the pump, having the features according to the preamble of the main claim, where such a pump is characterized in that the liquid delivery channel connected to the pump has a first stationary part made in the pump plug and a second part swinging around a generally horizontal axis, said second rotary part consisting of a tube having the end facing the first stationary part in the form of a generally spherical body whose outer surface is adapted to close the first stationary part of said delivery channel when said second part is substantially perpendicular to the first part.
According to a preferred embodiment of the invention the outer surface of the spherical body of the second swinging part of the delivery channel is made of a soft material adapted to warrant the tight closure of the delivery channel.
Moreover when the second swinging part is arranged in a position substantially perpendicular to the first part, the free end of said second part is lodged under the bellows push button thus preventing said bellows to be pressed down thus to actuate the pump and deliver the liquid unintentionally.
Therefore the invention carries out a delivery device attaining at the same time the object to close the liquid delivery duct and to block also the pump actuating means.